NFS/flexfiles: Remove dead code in ff_layout_mirror_valid()

nfs4_ff_alloc_deviceid_node() guarantees that if mirror->mirror_ds is
a valid pointer, then so is mirror->mirror_ds->ds.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
This commit is contained in:
Trond Myklebust 2019-02-28 11:35:33 -05:00
commit 29a23909e4